U.S. Pat. No. 3.859,527 describes a method for recording and reproducing a high-energy radiation image using a panel for storing a radiation image comprising a stimulable phosphor which emits light when stimulated with visible or infrared radiations after exposure to such radiation (wherein high-energy radiation means an electromagnetic wave or corpuscular radiation such as X-rays, .alpha.-rays, .beta.-rays, .gamma.-rays, neutrons, ultraviolet rays, or the like).
U.S. Pat. No. 4,258,264 describes a method and apparatus for reproducing a radiation image by stimulating a storing phosphor with stimulating rays, the wavelengths of which are in the range from 600 to 700 nm, and detecting the stimulated light by means of a light detector, the detected light being in the range from 300 to 500 nm.
EP 111,893 describes a method for recording and reproducing a radiation image comprising the steps of (i) causing a radiation image storing panel to absorb a radiation after passing through an object, such a panel containing a divalent europium activated barium fluorochloride phosphor, (ii) exposing said panel to an electromagnetic wave having a wavelength in the range from 400 to 550 nm to release the stored radiation energy as fluorescent light and (iii) detecting said fluorescent light.
EP 435,241 describes a phosphor for direct X-ray intensifying screen to be used in combination with a radiographic film comprising a mixture of europium doped barium fluorohalide and niobium doped yttrium metal tantalate.
EP 299,409 describes a radiographic intensifying screen to be used in combination with a radiographic film for direct radiography. The claimed phosphor comprises a mixture of a terbium activated rare earth oxysulfide phosphor and a terbium activated rare earth tantalate complex oxide phosphor.
JP 02/47,185 (1990) describes a method of preparation of a terbium activated rare earth tantalate complex oxide of formula: EQU (L.sub.1-n Tb.sub.n).sub.2 O.sub.3.xTa.sub.2 O.sub.5.yB.sub.2 O.sub.3.zNaF
wherein L is Y, La, Gd or Lu, n=0.005-0.1, x=0.95-1.05, y=0-5.0 and z is a number in order to have up to 0.52% by weight of NaF.
None of the above patent references relating to stimulable phosphors suggests the use of the terbium activated alkali metal tantalates of the present invention in order to obtain a green emitting photostimulable phosphor useful in a method similar to that described in the U.S. Pat. No. 3,859,527 and 4,239,968.